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GSE14668
Homo sapiens
27 Downloadable Samples
Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Hepatitis B virus (HBV)-associated acute liver failure (ALF) is a dramatic clinical syndrome due to a sudden loss of hepatic cells leading to multiorgan failure. The mechanisms whereby HBV induces ALF are unknown. We used gene expression profiling to establish a molecular definition of hepatitis B virus (HBV)-associated ALF. Two patients who underwent liver transplantation for HBV-associated ALF were studied. Gene expression profiling was performed on 8 liver specimens obtained from the two patients with ALF (4 samples per liver) and individual liver specimens from 8 liver donors and normal livers from 11 patients who underwent resection for angioma. Statistical analyses were used to identify the signature genes of HBV-associated ALF. Multivariate permutation analysis identified 1,368 transcripts that were differentially expressed in ALF; 709 were up-regulated and 659 down-regulated. The most represented up-regulated transcripts were those involved in the immune response, whereas the most abundant down-regulated transcripts were those involved in metabolism and hepatic synthesis. ALF was characterized by overriding B-cell signature comprising genes related to mature B cells and plasma cells with abundant polyclonal expression of immunoglobulin genes. By contrast, there was a limited T-cell signature and up-regulation of several inhibitors of T-cell activation. Immunohistochemical analysis confirmed the prominent B-cell signature showing diffuse liver infiltration by plasma blasts and plasma cells with strong cytoplasmic staining for IgM and IgG, associated with a significant deposition of complement factors. Using phage display technology, we demonstrated that the molecular target of the massive intrahepatic antibody response is the hepatitis B core antigen (HBcAg). These data suggest that the humoral immunity may exert a primary role in the pathogenesis of HBV-associated ALF.
Publication Title
B cell gene signature with massive intrahepatic production of antibodies to hepatitis B core antigen in hepatitis B virus-associated acute liver failure.
Sample Metadata Fields
Specimen part
View Samples- Rattus norvegicus
- 6 Downloadable Samples
- Affymetrix Rat Genome U34 Array (rgu34a)
Description
The assembly of the developmentally arrested primordial follicle and subsequent transition to the primary follicle are poorly understood processes critical to ovarian biology. Abnormal primordial follicle development can lead to pathologies such as premature ovarian failure. The current study used a genome-wide expression profile to investigate primordial follicle assembly and development. Rat ovaries with predominantly unassembled, primordial, or primary follicles were obtained. RNA from these ovaries was hybridized to rat microarray gene chips, and the gene expression (i.e., ovarian transcriptome) was compared between the developmental stages. Analysis of the ovarian transcriptome demonstrated 148 genes up-regulated and 50 genes down-regulated between the unassembled and primordial follicle stages. Observations demonstrate 80 genes up-regulated and 44 genes down-regulated between the primordial and primary follicle stages. The analysis demonstrated 2332 genes common among the three developmental stages, 146 genes specific for the unassembled follicles, 94 genes specific for the primordial follicles, and 151 genes specific for the primary follicles. Steroidogenic genes are up-regulated between unassembled and primordial follicles, and then many are again down-regulated between primordial and primary follicles. The hormones inhibin and Mullerian inhibitory substance (MIS) display a similar pattern of expression with the highest levels of mRNA in the primordial follicles. Several novel unknown genes that had dramatic changes in expression during primordial follicle development were also identified. Gene families/clusters identified that were up-regulated from unassembled to primordial follicles include growth factors and signal transduction gene clusters, whereas a down-regulated gene family was the synaptonemal complex genes associated with meiosis. Gene families/clusters that were up-regulated between primordial and primary follicles included immune response genes, metabolic enzymes, and proteases, whereas down-regulated gene families include the globulin genes and some steroidogenic genes. The expression of several growth factors changed during primordial follicle development, including vascular endothelial growth factor and insulin-like growth factor II. Elucidation of how these changes in gene expression coordinate primordial follicle assembly and the primordial to primary follicle transition provides a better understanding of these critical biological processes and allows selection of candidate regulatory factors for further investigation.
Publication Title
Alterations in the ovarian transcriptome during primordial follicle assembly and development.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 27 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Analysis of gene-expression profiles by microarrays can be very useful to characterize new potential candidate genes, key regulatory networks, and to define phenotypes or molecular signatures to improve the diagnosis or classification of the disease. We have used this approach in the study of one of the major causes of allergic diseases in Mediterranean countries, the olive pollen response, in order to find differential molecular markers among five clinical groups, Non-allergic, Asymptomatic, Allergic but not to olive pollen, Non-treated, olive pollen allergic patients and Olive pollen allergic patients (under specific-immunotherapy). The results of gene-expression by principal components analysis (PCA) clearly showed five clusters of samples that correlated with the five clinical groups. Analysis of differential gene-expression by multiple testing, and functional analysis by KEGG and Gene-Ontology revealed differential genes and pathways among the 5 clinical groups.
Publication Title
Differential gene-expression analysis defines a molecular pattern related to olive pollen allergy.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 42 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Analysis of gene-expression profiles with microarrays can be very useful to dissect specific responses and to characterize with a global view, new elements for improving the diagnosis, treatment and understanding of allergic diseases. We have used this approach for studying the olive pollen response, taking advantage our previous results of T-cell epitope mapping on Ole e 1 molecule (the major allergen from olive pollen) in order to analyze the stimuli influence on the gene-expression of olive pollen allergic patients. Peripheral blood mononuclear cells (PBMCs) from 6 healthy controls and 6 allergic subjects were stimulated 24 hours with olive pollen stimuli: Ole e 1 molecule and two Ole e 1 peptides previously defined as P2+3 (aa10-31), mainly recognized by non-allergic subjects (possible immunoregulatory epitope) and P10+12+13 (aa90-130), immunodominant T-cell epitope. RNA extracted from basal and stimulated PBMCs was analyzed by HuGeU133 plus 2.0 GeneChip, Affymetrix (38.500genes). After assessment of data quality by standard quality checks and principal components analysis (PCA), differential gene-expression by experimental conditions was performed by multiple testing, using microarrays specific software. Differences in functional analysis were performed by KEGG, for pathways and Gene-Ontology for biological process. The results of gene-expression by PCA showed differential clusters that correlated with the experimental conditions from samples of allergic patients. Analysis of differential gene-expression by multiple testing, and functional analysis by KEGG and Gene-Ontology revealed differential genes and pathways among the 4 experimental conditions.
Publication Title
Therapeutic targets for olive pollen allergy defined by gene markers modulated by Ole e 1-derived peptides.
Sample Metadata Fields
Specimen part, Disease
View Samples- Mus musculus
- 8 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
Expression of the SS18/SYT-SSX fusion protein is believed to underlie the pathogenesis of synovial sarcoma (SS). Recent evidence suggests that deregulation of the Wnt pathway may play an important role in SS but the mechanisms whereby SS18-SSX might affect Wnt signaling remain to be elucidated. Here, we show that SS18/SSX tightly regulates the elevated expression of the key Wnt target AXIN2 in primary SS. SS18-SSX is shown to interact with TCF/LEF, TLE and HDAC but not -catenin in vivo and to induce Wnt target gene expression by forming a complex containing promoter-bound TCF/LEF and HDAC but lacking -catenin. Our observations provide a tumor-specific mechanistic basis for Wnt target gene induction in SS that can occur in the absence of Wnt ligand stimulation.
Publication Title
The fusion protein SS18-SSX1 employs core Wnt pathway transcription factors to induce a partial Wnt signature in synovial sarcoma.
Sample Metadata Fields
Cell line
View Samples- Mus musculus
- 10 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
To investigate the impact of ablating Bcl9/Bcl9l on tumorigenesis, 6-8- week-old mice were exposed first to a single dose dimethylhydrazine (DMH, 44 mg/kg body weight), which is metabolized in the liver to carcinogenic azoxymethane (AOM), followed by 7 days oral administration of 2 % dextrane sulfate sodium (DSS) in the drinking water. This regimen results in the emergence of dysplastic adenomas, which progress to differentiated adenocarcinomas that are morphologically similar to human colorectal adenocarcinomas and typically harbor -catenin stabilizing mutations of GSK3 phosphorylation sites. Accordingly, these tumors present hallmarks of active Wnt signaling such as accumulation of nuclear -catenin and expression of Wnt target genes.
Publication Title
Bcl9/Bcl9l are critical for Wnt-mediated regulation of stem cell traits in colon epithelium and adenocarcinomas.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 133 Downloadable Samples
NextSeq 500
Description
The mammalian genome contains thousands of loci that transcribe long noncoding RNAs (lncRNAs), some of which are known to play critical roles in diverse cellular processes through a variety of mechanisms. While some lncRNA loci encode RNAs that act non-locally (in trans), emerging evidence indicates that many lncRNA loci act locally (in cis) to regulate expression of nearby genes—for example, through functions of the lncRNA promoter, transcription, or transcript itself. Despite their potentially important roles, it remains challenging to identify functional lncRNA loci and distinguish among these and other mechanisms. To address these challenges, we developed a genome-scale CRISPR-Cas9 activation screen targeting more than 10,000 lncRNA transcriptional start sites (TSSs) to identify noncoding loci that influence a phenotype of interest. We found 11 novel lncRNA loci that, upon recruitment of an activator, each mediate BRAF inhibitor resistance in melanoma. Most candidate loci appear to regulate nearby genes. Detailed analysis of one candidate, termed EMICERI, revealed that its transcriptional activation results in dosage-dependent activation of four neighboring protein-coding genes, one of which confers the resistance phenotype. Our screening and characterization approach provides a CRISPR toolkit to systematically discover functions of noncoding loci and elucidate their diverse roles in gene regulation and cellular function. Overall design: RNA-seq on A375 cells overexpressing candidate lncRNA or protein-coding gene.
Publication Title
Genome-scale activation screen identifies a lncRNA locus regulating a gene neighbourhood.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Homo sapiens
- 41 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
The objective of this study was to make use of gene expression signatures and functional assays to delineate differences between various intestinal colon carcinoma cell lines and normal intestinal epithelium to assess their appropriateness as a tumor model or for drug absorption studies.
Publication Title
Defining new criteria for selection of cell-based intestinal models using publicly available databases.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Mus musculus
- 24 Downloadable Samples
- Illumina HiSeq 2500
Description
Canonical Wnt signaling output is mediated by ß-catenin, which interacts with LEF/TCF transcription factors and recruits a general transcriptional activation complex to its C-terminus. Its N-terminus binds BCL9/9L proteins, which bind co-activators that in mammals contribute to fine-tuning the transcriptional output. We found that a BCL9/9L-dependent gene expression signature was strongly associated with patient outcome in colorectal cancer and that stem cell and mesenchymal genes determine its prognostic value. Abrogating BCL9/9L-ß-catenin signaling in independent mouse colorectal cancer models resulted in virtual loss of these traits, and oncogenic intestinal organoids lacking BCL9/9L proteins proved no longer tumorigenic. Our findings suggest that the BCL9/9L arm of Wnt-ß-catenin signaling sustains a stemness-to-differentiation equilibrium in colorectal cancer, which critically affects disease outcome. Mutational activation of the Wnt pathway is a key oncogenic event in colorectal cancer. Targeting the pathway downstream of activating mutations is challenging, and the therapeutic window is limited by intestinal toxicity. Contrasting with phenotypes caused by inactivating key Wnt pathway components, ablation of BCL9/9L proteins in adult mice indicated that they were dispensable for intestinal homeostasis, consistent with their role in tuning transcription. Cancer stem cells are increasingly recognized as responsible for tumor recurrence. The correlation between stemness traits in colorectal cancer models and BCL9/9L-ß-catenin signaling suggests that high Wnt signaling output is required for their maintenance. Our findings suggest that pruning Wnt-ß-catenin signaling might be well tolerated and prove sufficient for trimming stemness traits and improving disease outcome. Overall design: Examination of Bcl9/9l-knockout versus wild-type transcriptome in murine AOM-DSS tumors, APC-Kras tumors and healthy colocyte extracts.
Publication Title
BCL9/9L-β-catenin Signaling is Associated With Poor Outcome in Colorectal Cancer.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 3 Downloadable Samples
Description
RNA-seq and ATAC-seq data to understand how gene regulation and chromatin accessibility correlates with function enrichment in CRISPR screen for melanoma drug resistance
Publication Title
Genome-scale activation screen identifies a lncRNA locus regulating a gene neighbourhood.
Sample Metadata Fields
No sample metadata fields
View Samples